Boiler drum expansion joint assembly



y 1961 E. A. PEACOCK ET AL 2,990,818

BOILER DRUM EXPANSION JOINT ASSEMBLY 6 Sheets-Sheet 1 Filed Feb. 5, 1958 shun oqa on 0000000 00000000 o o mqa o o o o omo o oflmd u y 1961 E. A. PEACOCK ET AL 2,990,818

BOILER DRUM EXPANSION JOINT ASSEMBLY 6 Sheets-Sheet 2 Filed Feb. 5, 1958 July 4, 1961 E. A. PEACOCK ET AL 2,990,818

BOILER DRUM EXPANSION UOINT ASSEMBLY 6 SheetsSheet '3 gab 5914 Filed Feb. 5, 1958 0 Z m MM m x GORDON L/IVDSAY H/I/F'Vfy firm.

July 4, 1961 E. A PEACOCK ETAL 2,990,818

OILER DRUM EXPANSION JOINT ASSEMBLY 6 Sheets-Sheet 4 Filed Feb. 5, 1958 E. A. PEACOCK ETAL 2,990,818

BOILER DRUM EXPANSION JOINT ASSEMBLY July 4, 1961 6 Sheets-Sheet 5 Filed Feb. 5, 1958 Y m ha my 0 3 f July 4, 1961 E. A. PEACOCK ET AL 2,990,818

' BOILER DRUM EXPANSION JOINT ASSEMBLY Filed Feb. 5, 1958 I 6 SheecsSheet e United States Patent BOILER DRUM EXPANSION JOINT ASSEMBLY This invention relates to boilers and more particularly to means for sealing the expansion joints between the casing of a boiler and the drums .of the boiler.

In steam generators having a vapor and liquid drum and a liquid drum, the drums are connected to the boiler casing by connections or expansion joints which allow for the differential thermal expansions and contractions between the pressure parts of the boiler and the boiler casing. -In modern steam boilers where combustion air is supplied to :the combustion chamber of the boiler under a pressure above atmospheric pressure, leakage of combustion gases through the expansion joints is a problem, since such leakage causes pollution of the atmosphere of the boiler room. Heretofore, in order to prevent combustion gases from leaking through the expansion joints between the casing and the drums of the boiler, an outer air casing has been provided around the whole boilerorsealingboxes have been'constructed around the joints with the space between the casings or in the boxes maintained at a higher pressure .than the pressure in the combustion chamber. However, the aforesaid structures are expensiveand involved the weldingof an extra set'of plates or sealing bars to the drums of the boiler which welding-operation is bothdiflicult and expensive.

Accordingly, it is "an objectof this invention to provide relatively simple and inexpensive means for sealing the expansion joints between .boiler drums and the casing of the boiler against leakage of combustion gases from the combustion :chamber through the expansion joints.

\In :accordance with the present invention the drums of theboilers are connected to the boiler casing walls by means of novel expansion joint assemblies which allow for relative movement betweenthedrums and-casing and prevents leakage of combustiongases through-the-connections between the boiler drum and casing. Each ,expansion joint assembly comprises means for connecting the boiler drums to the casing so .that relative movement between the drum and:casing is permitted, and second means disposed adjacent to and in spaced relationship with said first means to define with the latter a substantially fluid-tight sealing ,chamber.

The expansion joint'assemblies, extending longitudinally of the drum for-connecting the casing to the drum, and the expansion joint assemblies extendingtransversally of the drum for connecting the casing side walls to the drum are connected :to each other in a substantially fluid-tight mannerwiththe sealing chambers of the longitudinally extending expansion joint assemblies being in communication withthesealing chamber of each of-the transversally extending expansion joint assemblies.

The sealing chambers of the expansion joint assemblies are supplied with a fluid under a pressure somewhat higher than the combustion gas pressure within the boiler to thereby prevent leakage of combustion gases through the expansion joints.

The invention will be more fully understood frorr'rthe following detailed description thereof when considered in connection with .theaccompanying drawings wherein two embodiments .ofthe invention are illustrated by way of example and in which:

FIG. 1 is a plan view, in elevation, of a boiler, with portions broken away, embodying expansion joint assemblies in accordance with the present invention; the

2,990,818 Patented July 4,- 1961 size of the expansion joint assemblies being exaggerated in relation to the size .of the boiler only for clarity;

FIG. 2 is a View in section taken substantially along line 22 of FIG. 1 with parts broken away for illustrationpnrposes;

FIG. 3 is a sectional view taken along line 3-3 of FIG. 1, with central portion broken away;

.FIG. 4 is a view in section taken along line 4-4 of FIG. 1, greatly enlarged;

FIG. 5 is a .view in section taken along line 5-5 of FIG. 1 and FIG. 9, greatly enlarged;

FIG. 6 is a sectional view taken substantially along line v66 of FIG. 2 on the same scale as FIGS. 4 and 5;

FIG. 7 ,is a fragmentary view in perspective of the longitudinally extending expansion joint assembly of this invention and the 'transversally extending expansion joint assembly according to this invention, for connecting the inclined casing roof portion and easing rear wall to the upper drum;

FIG. 8 is a fragmentary exploded view in perspective of the expansion joint assemblies shown in FIG. 7;

FIG. 9 is a fragmentary view in perspective of the longitudinally extending expansion assembly and the transversely extending expansion joint assembly according to this invention, for connecting the horizontal casing roof portion and casing front wall;

FIG. 10 is a fragmentary exploded view of the expansion joint assembliesshown in FIG. 9;

FIG. 11 is a fragmentary view in perspective of a longitudinally extending expansion joint assembly and a transversally extending expansion joint assembly, according to a second embodiment of this invention, showing the front casing wall and horizontal casing roof portion of the boiler;

FIG. 12 is a fragmentary end view of the transversally extending expansion joint assembly of the embodiment shown inzFIG. 11;

FIG. 13 is a view in section taken substantially along line 13-13 of FIG. 11 on the same scale as FIG. '12;

FIG. 14 is a sectional view taken along line -14-14 of FIG. 12;

FIG. 15 is a fragmentary view in perspective of the longitudinally extending expansion joint assembly according to a second embodiment showing the boiler rear walLand with parts broken away for illustration purposes;

16 is .a fragmentary perspective view ,of part of the expansion joint assembly shown in FIG. 15;

FIG. -17 is a fragmentary view in perspective of the arcuate sealing plate which forms a part of the expansion joint assembly shown in FIG. 15;

FIG. 1-8 is a view in section, similar to FIG. 13 but of the-longitudinally extending expansion joint assembly, according to the second embodiment of this invention, for connecting the inclined casing roof portion to the drum;v

,FIG. 19 is a fragmentary view of the arrangementof the expansion slots in the expansion joint assemblies which extend longitudinallyof the upper steam and water drum oftheboiler.

Referring ,now to the drawings and more particularly to FIGURES 1,2 and 3, eXpansi0n joint assemblies according to this invention are shown as applied by way of example to ,a conventional water tube steam boiler 10. Boiler 10 includes a setting comprising a front wall 11, rear wall 12 opposite side walls 13 and 14, a roof 15 and a floor '16. A combustion gas outlet 17 which communicates with a fine 18 is provided at the top of the setting adjacent side wall 14 for the discharge of combustion gases. A steam and water drum 19 is disposed horizontally in roof 15 and divides the roof into an inclined' roof. portion 20 and a fiat roof portion 21 which extends between the drum and flue '18. A water drum 22 is disposed horizontally in floor 16 and divides the v fioor into two sections. Upper drum 19 and lower drum 22 are interconnected by two spaced banks of substantially vertically extending steam generating tubes 23. A superheater 24, comprising a plurality of tubes 25 (FIG. 3), is disposed in the space between the two banks of tubes 23. Banks of tubes 23 define with side Wall 13, front wall 11, rear wall 12, roof 15 and floor 16 a combustion chamber 26 which is fired by a plurality of burners 27 in rear wall 12. The interior of combustion chamber 26 is lined by water wall tubes 28 which extend along fioor 16, side wall 13 and inclined roof portion 20. Front wall 11, rear wall 12, side walls 13 and 14, roof 15 and floor 16 are covered by a fluid-tight skin type casing which comprises front and rear wall portions 29 and 30 which overlie front and rear walls 11 and 12 respectively, two roof portions 31 and 32 which overlie roof portions 20 and 21, respectively, and floor portions 33 and 34 which are coextensive with the two sections of floor 16. Drums 19 and 22 extend horizontally to a point beyond front wall 11 and rear wall 12, as best shown in FIGS. 1 and 3.

Drum 22 is supported at the bottom by support members 35 while drum 19 is supported by steam generating tubes 23 so that upon thermal expansion and contraction of the pressure parts of boiler 10, namely, drums 19 and 22 and tubes 23 and 28, drum 19 will move vertically toward and away from drum 22. Drum 19 will also expand and contract longitudinally. To allow for relative movement between pressure parts of the boiler and the casing, drum 19 is fastened to the casing roof portions 31 and 32 and front and rear wall portions 29 and 30 by expansion joint assemblies according to this invention and hereinafter described.

To connect casing roof portion 31 to drum 19, an expansion joint assembly, generally designated by the reference numeral 36, is provided. As best shown in FIGS. 4 and 6, an elongated bar or bracket 37 which is L shaped in cross-section is welded to the side of drum 19 so that one arm 38 projects horizontally from the drum surface and the free arm 39 extends vertically and in spaced relationship with drum 19.

An angle iron 40 is positioned with one leg 41 adjacent the lower part of arm 39 of bar 37 and with the other leg 42 projecting from arm 39 at the same angle as the inclination of easing roof portion 31. Angle iron 40 is secured at leg 42 by a plurality of bolts 43 which pass through registered holes in leg 42 and casing roof portion 31. Leg 41 is provided with a plurality of longitudinally spaced elongated openings or slots 44 which are arranged and formed, as best shown in FIG. 19 and will be more fully described hereinafter. Openings 44 register with a first row of holes 45 which are arranged in spaced relationship to each other along arm 39 of bar 37. Leg 41 is secured to arm 39 by a plurality of bolts 46 which are passed through the aligned holes 44 and 45 and turned into nuts 47 which nuts are secured by welding to arm 39 and in alignment with holes 45. A gasket 48 is disposed between the adjacent surfaces of leg 41 of angle iron 40 and arm 39 of bar 37 to prevent gas leakage through the joint.

A second angle iron 49, having legs 50 and 51, is disposed adjacent the upper part of free arm 39 of bar 37 with leg 51 uppermost and projecting horizontally outward from bar 37 and leg 50 extending downwardly parallel to arm 39 of bar 37. Leg 50 has a plurality of spaced openings or slots 52 which are formed and arranged in a similar manner as openings 44 in angle iron 40, and which openings 52 register with a second row of spaced openings 53 in the upper part of arm 39. Bolts 54 are passed through each pair of aligned openings 52 and 53 and are turned into nuts 55 which are secured by welding to arm 39 and in alignment with holes 53. A gasket 56 is disposed between the adjacent surfaces of leg 50 and arm 39 to prevent gas leakage through the connection.

A sealing plate 57 which comprises a body portion or wall 58, an upper flanged portion 59 extending normal to body portion 58, and a lower inclined or sloping flanged portion 60 which projects from body portion 58 in an opposite direction from upper flange 59, is secured at lower flange portion 60 to casing roof portion 31 by a plurality of bolts 61 and at upper flange portion 59 to leg 51 of angle iron 49 by a plurality of bolts 62. Sealing plate 57 defines with arm 39 of bar 37 and angle irons 40 and 49 a substantially fluid-tight chamber 63. The end of sealing plate 57, adjacent rear casing wall 30, is provided with an outwardly extending flange 64 while a similar flange 65 (FIG. 6) is provided at the end of sealing plate 57 adjacent front casing wall 29.

As best shown in FIG. 5, drum 19 is connected to casing roof portion 32 by an expansion joint assembly 66 which is similar in construction to expansion joint assembly 36 and therefore like parts are designated by the same number but with the sufiix A added to the numerals. Expansion joint assembly 66 only differs from expansion joint assembly 36 in that the angular relationships between legs 41A and 42A of angle iron 40A is less than the angle between legs 41 and 42 of angle iron 40 of expansion joint assembly 36, and the angular relationship between flange portion 60A and body portion 58A of sealing plate 57A is less than the angle between flange portion 60 and body portions 58 of sealing plate 57. The lesser angular relationship between legs 41A and 42A and flange portion 60A and body portion 58A than the angle between the corresponding parts of expansion joint 36 is solely for the purpose of enabling leg 42A and flange portion 58A to lie flat against the surface of horizontal casing roof portion 32.

As best illustrated in FIGS. 6, 8 and 9, sealing plates 57 and 57A terminate at one end flush with the outer surface of rear casing wall 30 (FIG. 8) and at their opposite ends extend slightly beyond the outer surface of front wall 29 (FIGS. 6 and 9). Angle irons 40, 40A terminate at their opposite ends flush with the outer surfaces of front casing wall 29 and rear casing wall 30 (FIGS. 8 and 10) while angle irons 49 and 49A extend from a point flush with the outer surface of rear casing wall 30 (FIG. 6) and to a point slightly beyond front casing wall 30 (FIG. 8).

As shown in FIG. 19, slots 44 of angle irons 40 and slots 44A of angle iron 40A are arranged in three groups, A, B, and C, each group containing the same number of slots. The slots in group A are adjacent casing front wall 29, the slots in group C are adjacent casing rear wall 30, while the slots in group B are between the slots in groups A and C. Slots 44, and 44A in group A are inclined at an angle of 56 with the horizontal, while in group B the slots are inclined at an angle of 73 with respect to the horizontal and slots in group C extend vertically at to the horizontal. Slots 52 and slots 52A in angle irons 49 and 49A, respectively, are arranged in the same manner as slots 44 and 44A shown in FIG. 19. Slots 44, 52, 44A and 52A allow for relative expansion and contraction between casing roof sections 31 and 32 and drum 19 both in a horizontal direction, from rear wall 12 toward the front wall 11 of the boiler 10, and in a vertical direction.

To connect casing front wall 29 to drum 19, and expansion joint assembly 67 which extends transversely of drum 19 is provided. As best shown in FIGS. 1, 3, 6, 9 and 10, expansion joint assembly 67 comprises an arcuate plate 68 which is secured to the lower circumference of drum 19. Arcuate plate 68 is L-shaped in cross section and is welded to drum 19 along one leg 69 with the other leg 70 spaced from the drum and projecting outwardly from casing front wall 29. Plate 68 butts against and is secured by welding to the end of bars 37 and 37A of expansion joint assemblies 36 and 66. Plate 68 extends around the drum from 'the'top of arm 39 of bar 37 to the top of "arm 39A of bar 37A.

Casing firont'wall '29 has an arcuate shaped end edge which lies adjacent arcuate plate 68 (see .FIG. 3). To connect "the casing front wall 29 to plate 68, an arcuate shaped angle iron 71 is secured by a plurality of bolts 72 (FIG. 10.) to leg 70 of plate 68 and to casing front wall 29 by a plurality of bolts 200. .Angleiron 71 .isalso secured .at its opposite .end portions to angle irons 40' and 40A by bolts 73 which pass through holes in blocks 74. Each of the blocks 74 (FIG. is disposed at the end of angle irons 40 and 40A and .is secured as by welding between legs 41 and 42 of angle iron 40 and legs 41A and 42A of angle iron 40A. Angle iron 71 is provided with horizontally extending slots 75 (FIGS. 6 and 10) through which bolts 72 pass to secure angle iron 71 to plate 68. In addition angle iron 71 has vertically extending slots 76 through which bolts 200 .pass to secure angle iron 71 to front'wall 29. Slow 75 and 76 permit relative vertical and horizontal movement between drum 19, plate '68 which is carried by drum 19, and casing front wall 29. Circumferentially shaped sealing gaskets '77 are disposed between angle iron 71 and the outer surface ofcasing front wall 29, while a gasket 201 is disposed between angle iron .40 and leg 70 of plate 68.

As best shown in FIG. 9, a sealing plate 78.is disposed to overlie angle iron 71 and is secured to flanged end portions 65 vand65A of sealing plates 57 and 57A,.respectively, by .a plurality .of bolts 79A (only one .of which is shown in FIG. 6). Bolts 79A pass through holes 79 (FIGS. 6, '9 and 10) in sealing plate 78 and holes 80 in flanges 65 and 65A of sealing plates 57 and 57A. .As best illustrated in FIG. 10, sealing plate 78 has a face portion 81 and a body portion 82 which extends normal to face portion 81 and inwardly toward casing front wall .29. Body portion'82 terminates in a flange 83 which lies flat against the surface of easing front wall 29, while face .portion 81 lies against flanges 65 and 65A. Flange 83 is provided with a plurality of spaced holes 84 which regtister with holes 85 in casing front wall 29, the holes being adapted to receive bolts-86 (FIGS. 2 and 5) therethrough whereby sealing plate 78 is secured to casing front wall 29. Sealing plate 78 is secured toleg 70 of arcuate plate GS-by-means'ofan arcuate shaped angle iron-87. Angle iron 87 Plies in coextensivejrelationship with sealing plate -78rand is disposed with one leg 89 lying adjacent sealing plate 78 and the other leg 90 lying adjacent leg 70 0f arcuate plate :68.

Leg'89 is provided with a plurality of spaced elongated openings or slots "91 which extend vertically and lie in register with spaced holes 92 (FIG. 10) in face portion 81 of sealing plate 78. Bolts 93 (only one of which is 'shown in 'FIG. '6) ,pass through registered openings 91 :and92. Leg 910 of angle iron 87 is provided with apluralityof spaced elongated openings or slots 94 (FIGS. 9 and 10:) *Which extend'horizontally and register with holes 95 in leg :70 of arcuate plate 68. Bolts 96 (only one of which is shown in FIG. '6') are passed through aligned holes 94 and '95 .to secure leg 90 to leg 70 of arcuate .plate 68. Slo'ts-91and 94 in legs 89 and'90, respectively, of angle iron :87 permit relative horizontal and vertical movem'ent'of drum 19, plate 68 which is carried-by drum .19, and angle iron 87.

A gasket 202 is disposed between leg 89 of :anglciron I87 and face portion of-sealingplate 78 while a gasket 97 .is positioned between the adjacent surfaces of leg 90 of .angleiron :87 .andleg 70 of arcuate plate 68.

wSealing plate 78 and angle iron 87 define with leg 70 of alienate-plate 68 a substantially fluid-tight arcuate chamber. 98 (FIG. 6 )which communicatesat its opposite .endswith chambers 63 and 63A of "expansion joint assemblies 3.6 and 66.

- To-connectrear casing wall 30 to drum 19 and exp-ansion joint assembly 99 is provided, as bestshown in FIGS. 3, 7 and 8. An arcuate shaped bracket or plate 100 is 6 welded along one edge to the lowercircumference-of drum 19.. Tlate'100 extends normal to drum 19 and in overlapping r'elttionShip with rear casing wall 30. Plate abuts and is secured as by welding to the ends of bars 37 and 37A and terminates at the top edge of legs 39 and 39A 'of'bars'37 and 37A, respectively. The free edge portion of plate 100 overlaps casing rear wall 30 (FIG. 3) and is secured to casing rear wall 30 by a plurality of spaced fbolts .203 whichpass through vertically extending slots204 (FIG. '8). An 'arcuate'shaped sealing plate 101 which is U shaped in cross'section (FIG. 6) and having flanged edge portions '102 and 103 is disposed over the connecting .joint between casing rear wall 30 and plate 100. Flanged 'edge portion '102 is provided with a plurality of spaced holes 104 (FIGS. 6 and 8) which register with holes 105 (FIGS.:6 and 8) in flanged end portions 64 and 64A of sealing plates 57 and 57A and a plurality of holes 106 (FIG. 8) .in casing rear wall 30. Aligned holes 104 and 105, and 104 and '106 receive bolts 107 (only one of which is shown in FIG. 6) whereby sealing plate 101 is fixedly secured to scaling plates 57 and 57A and casing rear wall 30. Flanged edge portion 103 of sealing plate .101 is provided with a plurality of spaced holes 108 which register with vertically extending slots 109 in plate.100. Holes 108 and 109 receive bolts 110 therethrough (only one of which is shown in FIG. 6) to thereby slidably secure sealing plate 101 to plate 100.

As shown in FIG. 10, a gasket 111 is disposed between the adjacent surfaces of flange portion 102 and casing rear wall 30 and flanges 64 and 64A while between thesadjacent surfaces of flange portion 103 and plate .100 a gasket 112 is provided. Gaskets 111 and 112 provide a fluid-tight connection between sealing plate 101and casing rear wall 30, plate 100 and sealing plates 57 and 57A.

Sealing plate 101 defines with casing rear wall 30 a substantially fluid-tight chamber 113 which communicates at opposite ends with chambers .63 and 63A of roof expansion joint assemblies 36 and 66.

'Since rear wall 30 is fixed and drum 19 horizontally expands from rear wall 12 toward front wall 11, expan sion joint assembly 99 is adapted to allow only relative vertical movement between drum 19 and rear casing wall 30. Relative vertical movement'between rear casing wall 30 and drum .19 is achieved by bolts .110 sliding within vertical slots 109, as plate .100 is carriedvin .a vertical direction by drum 19.

As shown in FIG. 2, floor casing sections 33 and 34 are connected to lower drum 22 by expansion joint assemblies 114 and 115. Expansion joint assembly 114 comprises a bar or plate 116 which extends longitudinally of drum 22 and is welded alongone edge to the surface of drum 22 and projects substantially radially outwardly from the latter. The free edge portionof bar 116 overlaps the end of casing floor section 3 3. A sealing plate 117 which is 55 -U shaped in cross section andhas flanged edge portions 118 and 119, is disposed to overlie the overlapping portions of easing floor section 33 and plate 116. Sealing .plate 117 is secured alongflange portions 118 and 119 by a plurality of bolts (not shown) which pass through registered openings in flange portions 118 :and 1 19 and in casing floor -section 33 and plate 116. The openings in flange portion 119 which engages bar 116-are elongated toallow relative longitudinal movement of drum 22 and bar .116 which iscarried by drum 22.

Expansion joint assembly 11 5 which connects casing floor section 34 to drum 22 is identical in construction withexpansion;joint-assembly 114 and therefore will not be describedin .detail. The component parts of expansion .joint assembly which correspond to the compOnent parts of expansion joint assembly 114, have the same. reference character exceptthat the sufiix A has been added to .thenumerals. V

As shown in FIG. :3, front casing wall 2'9is connected todrum .22 by an expansion jointassembly 120which. is similar in construction to expansion joint assembly 67 except that provision is made for only horizontal relative movement between drum 22 and front casing wall 29 whereas expansion joint assembly 64, as aforedescribed, provides for vertical as well as horizontal relative movement between drum 19 and front casing wall 29.

Rear casing wall 39 is connected to lower drum 22 by an expansion joint assembly 121 which is similar to expansion joint assembly 99 which connects rear wall 30 to drum 19. Expansion joint assembly 120 differs from expansion joint assembly 99 in that no provision is made for either horizontal or vertical relative movement between drum 22 and casing rear wall 30.

Expansion joint assemblies114 and 115 are connected to expansion joint assemblies 120 and 121 in the same manner as expansion joint assemblies 36 and 66 are connected to expansion joint assemblies 67 and 99 for upper drum 19. The sealing chambers formed by sealing plates 117 and 117A of expansion joint assemblies 114 and 115 communicate with the sealing chambers formed by the sealing plates of expansion joint assemblies 120 and 121. The sealing chambers are maintained under a pressure above that of the pressure of the combustion gases in furnace chamber 16, by a fluid, as for example, air supplied to the sealing chambers by means such as a conduit 101A (FIG. 3) which is connected at one end to sealing plate 101 and communicates with the sealing chambers through sealing chamber 113, conduit 101A being connected at the other end to a fluid pump (not shown). Thus, with the pressure higher in the sealing chambers maintained above that in the furnace chamber 16, any leakage through the sliding connections will be of fluid into furnace chamber 16 rather than leakage of combustion products from the furnace chamber into the boiler room. Similarly, sealing chambers 63, 63A, 98 and 113 are maintained under a pressure above that of the pressure of the combustion gases in furnace chamber 16, by a fluid, as for example, air, supplied to the sealing chambers by means, such as a conduit 121A (FIG. 3) which .communicates at one end with the sealing chambers through the sealing chamber of expansion joint assembly 121, conduit 121A being connected at its other end to a fluid pump (not shown) to receive fluid from the latter. It is to be understood that more than one conduit may be provided to supply the fluid to the chambers surrounding drums 19 and 22 without departing from the spirit and scope of this invention. For example, a fluid supply conduit may be connected at one end to each expansion joint assembly and at the opposite end to the same or separate source of fluid under pressure.

As shown in FIGS. 4 and 6, bolts 46 and 54 pass through sleeves 205 which limit the extent of compression of the joint by tightening the bolts so that a tight joint is provided and at the same time relative movement is permitted between the members. Similarly, other bolts which connect members together between which members relative movement is desired, also pass through sleeves 205 although the sleeves may not be shown in the drawings.

Expansion joint assemblies, according to a second embodiment of the present invention, for connecting the upper drum to the boiler casing is shown in FIGS. 11 to 18, inclusive. The expansion joint assemblies according to the second embodiment of this invention while providing sealing chambers around the expansion joints connecting the casing to drum 19 is somewhat structurally simpler than the embodiment aforedescribed and illustrated in FIGS. 1 to 10, inclusive.

As shown in FIGS. 11, 13 and 15, casing roof portion '32 is connected to drum 19 by a longitudinal expansion joint assembly 122 which comprises an angle iron 123, similar to angle iron 40 (FIG. 4) of expansion joint assembly 36 and angle iron 40A (FIG. of expansion joint assembly 66, which is secured along one leg 124 to casing roof section 32 by a plurality of bolts 125 (FIG. 13) and secured along the other leg 126 to a leg 127 of a bar 128 by a plurality of bolts 129. Bar 128 cor.- responds to bar 37A of expansion joint assembly 66.

A second angle iron 130 is disposed, adjacent leg 124 of angle iron 123, with a leg 131 secured, as by welding, to casing roof portion 32 and extending upwardly from casing roof portion 32 parallel to leg 126 of angle iron 123 and with the other leg 132 extending away from drum 19 substantially parallel to casing roof portion 32.

A third angle iron 133, having legs 134 and 135, is disposed above and in spaced relationships to angle iron 123 and with leg 134 adjacent the upper portion of leg 127 of bar 128 and the other leg 135 projecting from leg 127 to a point over leg 132 of angle iron 130. Leg 134 of angle iron 133 is secured to leg 127 by a plurality of bolts 136 (only one of which is shown in FIG. 13) while leg 135 is secured to leg 132 of angle iron 130 by a plurality of bolts 137 (only one of which is shown in FIG. 13).

Interposed between the adjacent surfaces of leg 126 of angle iron 123 and leg 127 of bar 128, is a gasket 138. Another gasket 139 is disposed between the adjacent surfaces of leg 134 of angle iron 133 and leg 127 of bar 128 while a gasket 140 is disposed between the adjacent surfaces of legs 135 and 132 of angle irons 133 and .130, respectively. Also a gasket 141 is disposed between the adjacent surfaces of leg 124 of angle iron 123 and easing roof portion 32.

Angle iron 133 defines with angle irons 123 and 130 and leg 127 of bar 128 a substantially fluid-tight chamber 142 which extends the full length between casing front wall 29 and casing rear wall 30. Bolts 129 and 136 which secure angle irons 123 and 133 to leg 127 of bar 128 pass through elongated openings or slots which are formed and arranged in legs 126 and 134 of the angle irons 123 and 133 in the same manner as slots 44 and 52 of the irons 40 and 49, 40A and 49A of expansion joint assemblies 36 and 66 hereinbefore described and illustrated in FIG. 19. The slots permit relative vertical and horizontal movement between drum 19, bar 128 carried by drum 19, and easing roof portion 32.

As shown in FIG. 18, the expansion joint assembly 143 for connecting inclined casing roof section 31 to drum '19 is similar in construction to expansion joint assembly 122 which extends along the opposite side of drum 19. Since the component parts of expansion joint assembly 143 are similar to the parts comprising expansion joint assembly 1122, except that angular relationship of the legs of angle iron 123 of assembly 122 has been changed to adapt it for connection to an inclined surface, expansion joint assembly 143 will not be described in detail and parts thereof will be designated by the same reference numerals, as expansion joint assembly 122, with the suffix A added thereto.

As best shown in FIGS. l1, l2, and 14, front wall 29 is connected to drum 19 by an expansion joint assembly 144 which corresponds in purpose and function to expansion joint assembly '67 shown in FIGS. 1, 2, 9 and 10.

Expansion joint assembly 144 comprises an arcuate shaped angle iron or bar 145 (see FIG. 14) which is disposed adjacent casing front wall 29. Bar 145 corresponds to bar 68 of expansion joint assembly 67 (FIGS. 1, 2, 9 and 10) and is welded along one leg to the lower circumference of drum 19 and to the end of bar 128 and bar 128A of expansion joint assemblies 122 and 143, respectively. An angle iron 146 is connected along one leg to casing front wall 29 by a plurality of bolts 147 (FIG. 14) which pass through vertically elongated openings or slots 148 in angle iron 146 and openings 149 in casing front wall 29, openings 149 being in register with slots 148. Angle iron 146 is secured along its other leg to the free arm 149 of bar 145 by a plurality of spaced bolts 206 (only one of which is shown in FIG. 14) which pass through horizontally elongated openings or slots 150 in said other leg of angle iron 146 and openings 151 in mm 149, the openings 151 being in register with slots 150.

29, while slots 150 allow drum 19 and bar '145 to move horizontally withre'spect 'tocasing front wall 29.

Between the surface of angle iron'146 the adjacentfsurface of leg 149 of bar 145 and between angle iron "146 and the adjacent surface of casing front 'wall 29 is dis: posed gaskets 152 to prevent leakagebetween the aforesaidsurfaces. An arcuateshapedsealing plate 153, having a b'ody portion'154 and flanged e'dgeportions 155 and 156 which project normal to and in opposite directions from body portions 154, 'is disposed adjacent angle iron 146 withflange portion 155 lying next to the outer surface of easing front wall 29 and flange portion 1'56 spaced from angle iron 146 and extendingtoward arm 1490f bar 145. Flange edge portion 155 is secured to casing front wall 29 "by a plurality of spaced bolts 157 (FIG. 12) which pass through aligned holes in flange edge portion 155 and casingffront wall 29. As shown in FIG. '11 and 12, the

opposite ends of flange portion 155 are also secured to angle irons 130 and 130A of expansion joint assemblies 122 and 143, respectively by bolts 158. Bolts 158 pass through a hole adjacent each end of flange portion 155 and a hole in blocks 1'59 (seeFIG. 11 )'each of which are welded at the end-of angle irons 130 and -13'0A'between their respective legs.

'best seen in FIG. 14, flange 1561s secured to leg 1490f bar 145 by means of an arcuate shaped angle iron 1'60. Angle iron 160 is secured along one of its legs to flange edge portion 156 by a plurality of bolts 161 (FIG. 12) and is-secured to :leg 149 by a plurality of spaced bolts 162. Bolts .161 pass through vertically elongated openings or slots 163 (FIGS. 11 and "12) "in one leg of an'gle.i ron. 160, which slots 163 (1 1G514) register with holes .164 Lflange edge portion 156. Bolts 1362 pass through horizontally extending openings or slots .1 65 in the other leg of angle iron 160, which slots 165 register with holes 166 in arm 149 of bar 145-. Slots 163 and 165 allow relative horizontal and vertical movement of drum 19, and bar 145 which is carried by drum 19, and casing front wall 29.

The opposite end portions of angle iron 160 are also secured to angle irons 133 and 133A of expansion joint assemblies 122 and 144, respectively. The ends of the angle irons 133 and 133A adjacent casing front wall 29 are each closed by a block 167 (FIG. 11) which blocks are disposed between and welded to the respective legs of the angle irons. Blocks 167 are each provided with a bolt hole (not shown) which registers with the endmost slot 163 in angle iron 160. Each end of angle iron 160 is secured to block 1 67 and sealing plate 153 by a bolt 168 (FIG. 12) which passes through the slot 163 and a hole in leg 156 of sealing plate 153 and the bolt hole in block 167.

A gasket 169 is disposed between the adjacent surfaces of angle iron 160 and leg 156 of sealing plate 153 While another gasket 170 is disposed between the adjacent surfaces of angle iron 160 and arm 149 of bar 145.

With sealing plate 153 secured to bar 145 and casing front wall 29, as aforedescribed, sealing plate 153 defines with angle iron 146, arm 149, and casing front Wall 29 a substantially fluid-tight chamber 121 which communicates at its opposite ends with chambers 142 and 142A of expansion joint assemblies 122 and 144, respectively.

To connect casing rear wall 30 to drum 19, an expansion joint assembly 172 is provided which assembly is illustrated in FIGS. l5, l6 and 17. Expansion joint assembly 172 comprises arcuate shaped plate 173, similar to plate 100 of expansion joint assembly 99, which is welded along one edge to the lower surface of drum 19 and projects normal to the surface of drum 19. Plate 173 abuts and is welded adjacent its opposite end portions to ends of bars 128 and 128A and overlaps casing rear wall 30 as shown in FIG. 16. Casing rear wall 30 and plate 173 are secured together by a plurality of bolts 174 (see FIG. 13) which pass through vertically extending "1 0 slots 175-(FIG. 16) in casingrear wall 30 and holes (not shown) in plate 173.

An ar'cuate shaped sealing plate 176 (FIG. 17) U shaped in cross section and having flanged edge portions 177 and 1'78,is disposed over the joint between plate 173 and easing rear wall 30. The opposite ends of the U shaped body portion of plate 176 is closed by blocks 179; Sealing plate 176'is secured to plate 173 by a plurality of bolts 180 (two of which are shown in FIG. 13), which pass through vertically extended slots 1'81in flangedportion 177 and holes 182 (FIG. 16) in plate173, slots 181 being in register with holes 182. "Sealing plate 176 is secured to 'casing rear wall Why a plurality of bolts183, (two of which are shown 'inFIG. "1 13) which pass through holes 184 in flange 178 and holes (not'shown) in'casin'g rear wall 30, the holes 184 and the holes 'in casingrear wall being in register. Sealing plate 176 is "also conf necte'd at blocks 179 to legs 135 and 135A ofangle-irons 13 3 and 133A of expansion joint assemblies 122 and 143 by means of bolts 184 (FIGS. 13 and 18) which pass through holes 185 'in-leg 1 35 and leg 135A and a ho'le'in each of 'the blocks 179. The opposite end portions of flange 178 of sealing 'pla'te 17 6 arealso connected to blocks 186 and 186A which are disposed between and welded to legs 131 and 132 of angle iron 130 and legs 1-3 1'A-'an'd 132A of angle iron 130A. *Bolts 187 and 187A pass through holes in blocks 186 and 186A, which holes register with the endmost hole 184 in flange portion 178 of sealingplate17'6.

Between the adjacent surfaces of flange 177 of sealing 'plate'176 and plate'173 'is disposed 'a sealing gasket 1 88 while *anothersea'linggas'ket'189 isdisposed between flange 178-of'sealing plate 176 and casing rear wall '30. Sealing gasketsf188 and 189 are effective to prevent fluid leakage through the joints. "Sealing plate 176 defines with casing rear wall 30 and plate 173, a substantially fluid-tight chamber which communicates at the opposite ends with sealing chambers 142 and 142A of roof expansion joint assemblies 122 and 143.

Slots 181 in flange 177 of sealing plate 176 allow relative vertical movement of drum 19, plate 173 which is carried by drum 19, and sealing plate 176. For example, as drum 19 is moved upwardly under expansion of the pressure parts of the boiler, plate 173 will be carried upwardly by drum 19 and bolts 180 will move upwardly in slots 181 in flange 177 of sealing plate 176, while the bolts 174 are carried upwardly in slots 175 in casing rear wall 30 by plate 173.

Sealing chambers 142, 142A and 171 of expansion joint assemblies 122, 143 and 144, respectively, as well as the sealing chambers of expansion joint assembly 172, are maintained under a pressure above that of the pressure of the combustion gases in the furnace chamber 26 by a fluid, such as air, supplied to the chambers by suitable means, as for example, a conduit 171A connected at one end to a pump (not shown) and connected at the other end to sealing plate 154 of expansion joint assembly 144 (see FIGS. -11 and 12). It is to be understood that the fluid may be supplied to the sealing chambers of expansion joint assemblies 142, 142A, 171 and 172 by more than one conduit without departing from the spirit and scope of this invention. For example, a conduit may be provided for each expansion joint assembly to supply fluid to the sealing chambers thereof, which conduits are connected at their opposite ends to the same source or separate sources of fluid under pressure.

It is believed readily apparent that the present invention provides novel expansion joint assemblies for connecting the casing of a boiler to the boiler drums wherein each expansion joint assembly provides a fluid-tight sealing chamber adjacent the connection between the casing and the drum. The expansion joint assemblies, while constructed and arranged to allow relative movement between the casing and a drum, are connected to each other in a fluid-tight manner with no relative movement there between, and with the sealing. chambers of one expansion *11 joint assembly being in communication with another of the expansion joint assemblies so that all of the sealing chambers may be maintained under pressure from the same source of fluid. v p Although, two embodiments of the invention have been illustrated and described in detail, it is to be expressly understood that the invention is not limited thereto. Various changes can be made in the arrangement of parts without departing from the spirit and scope of the inven- ,tion, as the same will now be understood by those skilled in the art.

What is claimed is: e In a vapor generator having a drum disposed partly in a substantially horizontally extending wall of the setting to divide said wall into two sections and projecting beyond'two opposite walls of the setting, and wherein said setting includes an outer fluid-tight casing, the invention comprising a first expansion joint assembly which comprises a first connecting means for connecting one side of said drum to one section of the horizontally extending casing wall section and for allowing relative movement between said drum and casing, a first sealing means disposed to overlie the expansion joint formed by said first connecting means in spaced relationship to said joint to define a sealing chamber, said first sealing means being secured to the casing and connected to said connecting means for movement relative to the latter; a second expansion joint assembly which comprises a second connecting means for connecting the other side of said drum to the other section of the horizontally extending casing wall section and for allowing relative movement between said drum and easing, a second sealing means disposed to overlie the expansion joint formed by said second connecting means in spaced'relationship to said joint to define a second sealing chamber, said second sealing means being secured to the casing and connected to said second connecting means for movement relative to the latter; a third expansion joint assembly which comprises a third connecting means for connecting the drum to the casing of one of said opposite walls and for allowing relative movement between the casing and said drum, a third sealing means disposed to overlie the expansion joint formed by said third connecting means in spaced relationship with said joint to define a third sealing chamber, said third sealing means being secured to the casing and connected to said third means for movement relative to the latter; a fourth expansion joint assembly which comprises a fourth connecting means for connecting the drum to the casing of the other of said opposite walls and for allowing relative movement between the casing and said drum, a fourth sealing means disposed to overlie the expansion joint formed by said fourth connecting means in spaced relationship with said joint to define a fourth sealing chamber, said fourth sealing means being connected to said fourth means for movement relative to the latter; said third sealing means being secured in a fluidtight manner to said second sealing means and said first sealing means so that the third sealing chamber communicates with said first and second sealing chambers, said fourth sealing means being secured in a fluid-tight manner to said first and second sealing means so that the fourth sealing chamber communicates with the first and second sealing chambers, and means for maintaining a pressure in said first, second, third and fourth sealing chambers above the combustion gas pressure in the setting.

References Cited in the file of this patent UNITED STATES PATENTS 1,920,740 Black Aug. 1, 1933 2,774,340 Iankowski Dec. 18, 1956 2,864,344 Artsay Dec. 16, 1958 

